Development of a vortex-assisted switchable-hydrophilicity solvent-based liquid phase microextraction for fast and reliable extraction of Zn (II), Fe (II), Pb (II), and Cd (II) from various baby food products.

This manuscript describes the development of a novel liquid phase microextraction (LPME) method for the extraction and determination of Zn (II), Fe (II), Pb (II), and Cd (II) in various infant/baby food and supplements products. The method is based on vortex-assisted extraction combined with a switchable-hydrophilicity solvent (SHS) sample preparation. The SHS, which undergoes reversible phase changes triggered by pH change, enables selective extraction and easy phase separation. A flame atomic absorption spectroscopy was used in the final determination step. Optimization studies revealed, that the optimal pH of the sample solution (after digestion) during analytes extraction is 5.5. A l-proline is added to the sample (375 mM) to ensure the complexation of the target metal cations. After the complexation step, 750 µL of SHS - a N, N-Dimethylcyclohexylamine along with 0.9 mL of 2 M of acetic acid solution is added (hydrophilicity switch-on stage) and mixed manually to obtain a homogeneous solution. In the last stage, 0.45 mL of 10 M NaOH solution (hydrophilicity switch-off stage) is added to the sample solution and a vortex for 100 s is applied to ensure the effective extraction and separation of the complex containing the analytes. At this stage, a cloudy solution is immediately obtained. Finally, the effective phase separation is obtained at the centrifugation step (4000 rpm for 2 mins). The method limit of detection was as 0.03, 0.009, 0.6, and 0.2 ng/L for Zn (II), Fe (II), Cd (II), and Pb (II) respectively with RSD% below 2.0 %. The analysis of certified reference materials and real samples proved the full applicability of the method for routine analysis, contributing to the field of heavy metal analysis and ensuring the safety of baby products. According to the AGREE methodology, this method can be named as green analytical chemistry method with a score of 0.77.

An air-assisted dispersive liquid phase microextraction method based on a hydrophobic magnetic deep eutectic solvent for the extraction and preconcentration of melamine from milk and milk-based products.

In the current research, a fast and sustainable air-assisted hydrophobic magnetic deep eutectic solvent-based dispersive liquid phase microextraction followed by UV-Vis spectrophotometry measurements was optimized for the extraction and determination of melamine in milk and milk-based products. The central composite design was applied for the optimization of factors affecting the recovery of melamine. Quantitative extraction of melamine was achieved using hydrophobic magnetic deep eutectic solvents prepared from a mixture of octanoic acid, aliquat-336, and cobalt(II) chloride. The optimum conditions for extraction were found as follows: 6 extraction cycles, pH 8.2, extraction solvent volume 260 µL, and acetone volume 125 µL.Interestingly, a centrifugation step was not required to achieve phase separation. Under the optimum conditions, melamine was determined in the linear range of 3-600 ng mL-1, the limit of detection (3Sblank/m) of 0.9 ng mL-1, and the enrichment factor of 144. The validation of the method was investigated by the analysis of reference materials. Consequently, the method was successfully applied for the analysis of melamine residues in milk and milk-based products.

Removal of food dyes from aqueous solution by chitosan-vermiculite beads.

In this study, Chitosan (Ch)-Vermiculite (V) composite beads material which is a low-cost and naturally effective adsorbent were used for efficient removal of Sunset Yellow FCF (Sy) and Brilliant Blue FCF (Bb) food dyes from aqueous solution. Ch-V composite beads were characterized by using FTIR, SEM, XRD and PZC analysis. The adsorbent properties of Ch-V composite beads for Sy and Bb dyes were evaluated in terms of pH, concentration, kinetic (time) and thermodynamic (temperature) of adsorption. The experimental data presented were obtained from Langmuir, Freundlich and Dubinin-Radushkevich (DR) isotherm models. The maximum adsorption capacity for the Langmuir equation was found to be 0.387 mol kg-1 for Sy and 0.229 mol kg-1 for Bb, respectively. The results showed that the experimental data were better fit the Langmiur model for Sy and the Freundlich model for Bb. Adsorption energies obtained from DR model for Sy and Bb showed that adsorption processes were chemically. The pseudo-second order and intra-particle diffusion models of adsorption kinetics are in accordance with Sy and Bb. As a result of thermodynamic evaluation of Sy and Bb adsorption, it was found that adsorption processes were endothermic, entropy increased and reaction was spontaneous.

Effective UO22+ removal from aqueous solutions using lichen biomass as a natural and low-cost biosorbent.

The UO22+ biosorption properties of a lichen, Evernia prunastri, from aqueous solutions were investigated. The widely occurring lichen samples were collected from the forest in Bilecik-Turkey. The UO22+ biosorption onto lichen was characterized by FT-IR and SEM-EDX analysis techniques before and after biosorption. The effects of the solution pH, biosorbent dosage, UO22+ concentration, contact time, and temperature on UO22+ biosorption on lichen sample were studied by using the batch method. The isotherm experimental data were described using isotherm models of Langmuir, Freundlich and Dubinin Radushkevich. The maximum UO22+ biosorption capacity of the lichen sample was estimated by the Langmuir equation to be 0.270 mol kg-1. The adsorption energy from the Dubin Radushkevich model was found to be 8.24 kJ mol-1. Kinetic data determined that the biosorption was best described by the pseudo-second-order kinetic model. Thermodynamic findings showed that the biosorption process was endothermic, entropy increased and spontaneous. In conclusion, the lichen appears to be a promising biosorbent for the removal of UO22+ ions from aqueous solutions because of high biosorption capacity, easy usability, low cost, and high reusability performance.

Sequential determination of serum viral titers, virus-specific IgG antibodies, and TNF-α, IL-6, IL-10, and IFN-γ levels in patients with Crimean-Congo hemorrhagic fever.

BACKGROUND: Although there have been a number of studies on the pathogenesis of Crimean-Congo hemorrhagic fever (CCHF) recently, knowledge on this topic is still insufficient. This study aims to reveal the kinetics of serum CCHF virus (CCHFV) titers, serum levels of anti-CCHFV immunoglobulin (Ig)G, tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, and interferon (IFN)-γ in CCHF patients. METHODS: In total, 31 CCHF cases (11 fatal) were studied. Serum samples were obtained daily from all patients from the time of admission and continued for a 7-day hospitalization period for serologic (ELISA), virologic (real-time PCR), and cytokine (ELISA) analysis. RESULTS: The mean serum CCHFV titer at admission was 5.5E + 09 copies/mL in fatal cases and 5.7E + 08 copies/mL in survivors (p < 0.001). Compared to survivors, both the mean serum levels of IL-6 and TNF-α at admission were found to be significantly increased in fatal cases. The serum levels of IL-6, TNF-α and serum CCHFV titer at admission were significantly and positively correlated with disseminated intravascular coagulation (DIC) scores (r = 0.626, p = 0.0002; r = 0.461, p = 0.009; and r = 0.625, p = 0.003, respectively). When the data obtained from the sequential determination of CCHFV titer and levels of anti-CCHFV IgG, IL-6, TNF-α, IL-10 and IFN-γ were grouped according to the days of illness, the initial serum CCHFV titer of a fatal patient was 5.5E + 09 (copies/mL) and it was 6.1E + 09 (copies/mL) in a survivor on the 2 day of illness. While significant alterations were observed in all cytokines during the monitoring period, IL-6 levels remained consistently higher in fatal cases and TNF-α levels increased in both in fatal and non-fatal CCHF cases. CONCLUSIONS: The increased CCHFV load and higher concentrations of IL-6 and TNF-α, the presence of DIC, and the absence of CCHFV specific immunity are strongly associated with death in CCHF.

Antioxidant activities, metal contents, total phenolics and flavonoids of seven Morchella species.

Seven Morchella species were analyzed for their antioxidant activities in different test systems namely beta-carotene/linoleic acid, DPPH, reducing power, chelating effect and scavenging effect (%) on the stable ABTS*(+), in addition to their heavy metals, total phenolic and flavonoid contents. In beta-carotene/linoleic acid system, the most active mushrooms were M. esculenta var. umbrina and M.angusticeps. In the case of DPPH, methanol extract of M. conica showed high antioxidant activity. The reducing power of the methanol extracts of mushrooms increased with concentration. Chelating capacity of the extracts was also increased with the concentration. On the other hand, in 40 microg ml(-1) concentration, methanol extract of M. conica, exhibited the highest radical scavenging activity (78.66+/-2.07%) when reacted with the ABTS*(+) radical. Amounts of seven elements (Cu, Mn, Co, Zn, Fe, Ca, and Mg) and five heavy metals (Ni, Pb, Cd, Cr, and Al) were also determined in all species. M. conica was found to have the highest phenolic content among the samples. Flavonoid content of M. rotunda was also found superior (0.59+/-0.01 microg QEs/mg extract).

Determination of in vitro antioxidative and antimicrobial properties and total phenolic contents of Ziziphora clinopodioides, Cyclotrichium niveum, and Mentha longifolia ssp. typhoides var. typhoides.

The aerial parts of Ziziphora clinopodioides, Cyclotrichium niveum, and Mentha longifolia ssp. typhoides var. typhoides were screened for their possible antioxidant and antimicrobial activities in addition to their penolic contents. Antioxidant activity was employed by two complementary test systems: 2,2'-diphenyl-1-picrylhydrazyl free radical scavenging and beta-carotene/linoleic acid. In the first case, Z. clinopodioides was superior to the other species with a 50% inhibitory concentration value of 37.73 +/- 1.18 microg/mg. Similar results were obtained from the beta-carotene/linoleic acid system. Inhibition capacity of the linoleic acid of Z. clinopodioides was 83.56 +/- 1.19%. Additionally, antioxidant activities of butylated hydroxytoluene, curcumin, and ascorbic acid were determined in parallel experiments. Methanol extracts obtained from the plants studied were found to have moderate antimicrobial activity against all microorganisms tested. In general, Z. clinopodioides extract exhibited stronger activity than the other extracts. On the other hand, Acinetobacter lwoffii and Candida krusei were the most sensitive microorganisms for the all extracts. The amount of the total phenolics was highest in Z. clinopodioides extract (129.55 +/- 2.26 microg/mg), followed by M. longifolia ssp. typhoides var. typhoides (93.47 +/-1.84 microg/mg). It is extremely important to note that there is a positive correlation between antioxidant activity potential and amount of phenolic compounds.

Determination of the antimicrobial and antioxidative properties and total phenolics of two "endemic" Lamiaceae species from Turkey: Ballota rotundifolia L. and Teucrium chamaedrys C. Koch.

This study was designed to examine the in vitro antimicrobial and antioxidant activities and the amount of total phenolics of the methanol extracts of Ballota rotundifolia L. and Teucrium chamaedrys C. Koch. In the case of antimicrobial activity tests, polar sub-fractions of the methanol extracts of plant species exhibited weakest antimicrobial activity when compared with the non-polar ones. While, non-polar sub-fraction of B. rotundifolia showed moderate activity against A. lwoffii, C. perfringens and the yeasts, T. chamaedrys performed excellent activity pattern against all of the tested microorganisms. The sub-fractions were also screened for their possible antioxidant activities by two complementary tests, namely DPPH free radical-scavenging and beta-carotene/linoleic acid assays. Non-polar extracts of the plant species remained inactive in both test systems. On the other hand polar extracts showed remarkable antioxidant activities. In DPPH system, free radical scavenging effect of T. chamaedrys was measured as 18.00 +/- 1.42 microg.mg(-1). It is extremely important to point out that, polar sub-fraction of T. chamaedrys is found as effective as the positive control BHT. Non-polar sub-fraction of T. chamaedrys found to have the highest total phenolic amount (97.12 +/- 1.28 microg/mg). Results obtained from this experiment confirm the relationship between the amount of phenolics and biological activities.

Investigation of acute effects of aflatoxin on rat proximal and distal colon spontaneous contractions.

Aflatoxins are one of the most potent toxic, mutagenic, teratogenic, cancerogenic, and immunosuppresive substances that naturally occurring contaminants of food. There are some studies in various animal species that have reported aflatoxin effects on gastrointestinal systems, but acute effects of aflatoxins have not been clearly investigated. In this study, we aimed to investigate the acute gastrointestinal effects of total aflatoxin on rat isolated proximal and distal colon. Aflatoxin was given cumulatively at 10(-8)-10(-5)M concentrations and the amplitude and frequency of proximal and distal colon contractions were increased significantly. In the presence of atropine sulfate (23.6 nM) and morphine (0.3 microM) the amplitude and frequency of aflatoxin induced spontan contractions in the proximal and distal colon decreased significantly, on the other hand, L-NNA (0.3 microM) increased contractions' amplitude and frequency significantly in the proximal colon but not in the distal colon. In conclusion, aflatoxin may increase the amplitude and frequency of contractions by increasing muscarinic activity or by decreasing NO synthase and/or release in proximal colon and by increasing muscarinic activity in the distal colon. These findings of aflatoxin on isolated rat proximal and distal colon may explain their acute gastrointestinal effects in humans and animals.

Changes in spontaneous contractions of rat ileum by aflatoxin in vitro.

Aflatoxins are a group of mycotoxins produced by toxigenic strains of Aspergillusflavus, Aspergillusparasiticus and Aspergillusnomius as secondary metabolites. Most of the studies on the aflatoxins have focused mainly on their chronic toxic effects but aflatoxins have also a lot of acute effects on the respiratory, cardiovascular and gastrointestinal systems. In this study the acute gastrointestinal effects of the aflatoxins on rat isolated ileum and the possible mechanisms underlying contractile responses to them were investigated. Aflatoxin increased both of the amplitude and the frequency of spontaneous contractions in a dose-dependent manner. Pretreatment with a cholinergic system inhibitor, atropine sulfate (23.6nM), a specific sodium-channel blocker, tetrodotoxin (0.3microM) and an inhibitor of ACh release from terminal motor neurons, morphine (0.3microM) decreased both of aflatoxin induced spontaneous contractions' amplitude and frequency, in contrast a nicotinic ganglionic blocker, hexamethonium chloride (55microM) did not change the aflatoxin effect. But the decrease of amplitude was more than the frequency in the presence of these antagonists. In conclusion, these findings of aflatoxin on isolated rat ileum may explain their acute gastrointestinal effects in humans and animals.